Diabetes Report

U.S. Patients Improved Diabetes Control Over 5-Year Period

The Quest Diagnostics Diabetes Report shows that people with diabetes are doing a better job of managing their disease.

The proportion of test results deemed to represent good diabetes control increased from 36% in early 2001 to a high of 56% in late 2005.

Seasonal variation was observed with peak concentrations in winter months. This seasonal variation in HbA1c has been described and may be linked to decreased activity levels and higher food intake associated with the winter holidays.

The test for hemoglobin A1c (HbA1c) is a key indicator of diabetes control. It measures the amount of sugar attached to hemoglobin, the primary protein in red blood cells, and indicates a patient’s average blood sugar level over the previous two to three months. The American Diabetes Association recommends that people with diabetes maintain their hemoglobin A1c levels below 7% of the total hemoglobin in red blood cells.

PATIENTS IMPROVED DIABETES CONTROL OVER 5-YEAR PERIOD, BUT MANY FAIL TO ACHIEVE TREATMENT GOAL

-- Quest Diagnostics Health Trends™ Diabetes Report is based on 14.3 million test results from 2001 – 2005 from the nation’s largest database of clinical lab results--

LYNDHURST, NJ, May 3, 2006 – People with diabetes who visit health professionals are doing a better job of managing their disease, according to results from the Quest Diagnostics Health Trends™ Diabetes Report. However, the Report also found that nearly half of all test results in 2005 were still above the target goal for diabetes control set by the American Diabetes Association (ADA).

The Health Trends™ Diabetes Report is based on 14.3 million hemoglobin A1c test results performed from 2001 through 2005 by Quest Diagnostics laboratories in the United States on patients whose physicians classified them as having diabetes through the use of specific diagnostic (ICD-9) codes. The proportion of test results deemed to represent good diabetes control increased from 36 percent in early 2001 to a high of 56 percent in late 2005, according to the Quest Diagnostics Report.

Quest Diagnostics Health Trends™ reports identify and track disease and wellness benchmarks. They are made available as a public service to inform patients, health professionals, and policy-makers about the current status of the nation’s health. The Diabetes Report is the second in the series of Health Trends™ reports, following the Heart Health Report on LDL cholesterol levels, which Quest Diagnostics issued in October 2005.

The test for hemoglobin A1c (HbA1c) is a key indicator of diabetes control. It measures the amount of sugar attached to hemoglobin, the primary protein in red blood cells and indicates a patient’s average blood sugar level over the previous two to three months. The ADA recommends that people with diabetes maintain their hemoglobin A1c levels below 7 percent of the total hemoglobin in red blood cells. The Health Trends™ Diabetes Report showed that the average hemoglobin A1c test result decreased from 7.8 percent of total hemoglobin in January 2001 to 7.2 percent in December 2005. This represents a drop of 8 percent.

“What makes these data so interesting is that they suggest that over time, glucose control is getting better,” said Nathaniel G. Clark, M.D., M.S., R.D., National Vice President, Clinical Affairs, American Diabetes Association. “This is in direct contrast to the National Health and Nutrition Examination Survey (NHANES) data which suggests that diabetes control in the United States population declined through the period of the late 1990s. NHANES provides the context that makes the Quest Diagnostics data from the last five years so interesting.”

“These results are a great contribution to our understanding of the state of diabetes care and outcomes in the United States,” said Francine R. Kaufman, M.D., professor of pediatrics at the Keck School of Medicine, University of Southern California, and past president of the ADA. “They indicate that diabetes care has improved over the last five years with glucose-lowering agents, a push to multidisciplinary care, stricter criteria for diabetes diagnosis and public and professional awareness campaigns about the importance of early diagnosis and treating to target.”

“Possible explanations are greater awareness of both the use of and goals for HbA 1c, frequency of HbA 1c testing and better use of available medications,” said Dr. Clark, of the ADA.

The number of test results included in the Health Trends™ Diabetes Report is more than one hundred times that of other published reports on diabetes health. “This is a huge data set with enormous statistical power that helps us understand the state of control of diabetes in the United States,” said David E. Goldstein. M.D., Professor Emeritus, University of Missouri Health Sciences Center, the first director of the national standardization program for HbA 1c and principal investigator for the landmark Diabetes Control and Complications Trial. “This is valuable information for healthcare professionals, policy makers and payers.”

“The Quest Diagnostics database not only is larger than any of the existing research studies but also provides more current data,” said Josef Coresh, M.D., Ph.D., Professor of Epidemiology, Biostatistics & Medicine, Johns Hopkins University.

Most of the improvement in HbA 1c results was observed within the first three years encompassed by the report. The reason for the slow-down in improvement in 2004 and 2005 is not known, but it could be attributed, at least in part, to the difficulty in getting closer to the goal as HbA 1c results decrease. “As one approaches a HbA 1c level of 7 percent it becomes harder and harder to make improvements,” Dr. Clark said. “Moving from 10 percent to 9 percent is far easier than moving from 8 percent to 7 percent or lower.”

On average, patients were tested 1.9 times per calendar year. This average testing frequency was the same in each of the five years. The ADA recommends that patients with stable diabetes control have their HbA 1c measured twice a year. The vast majority of these tests were ordered by physicians in an office setting.

Another significant finding from the Quest Diagnostics Health Trends™ Diabetes Report is seasonal variation in HbA 1c, with peak levels in winter months (December through February). This seasonal variation in HbA 1c has been described. Climate and the decreased activity levels and higher food intake associated with the winter holidays have been mentioned as possible causes.

Diabetes is a growing health concern in the United States. More than 14 million Americans are currently diagnosed with diabetes and an additional 6 million may have diabetes and not know it, according to the U.S. Centers for Disease Control and Prevention. Diabetes is a chronic condition in which the body does not produce or properly use insulin to convert sugar into energy. If poorly managed or undiagnosed, diabetes may lead to serious complications including heart attack, stroke, blindness, amputation and kidney failure.

“There is a serious need for clinical baselines to determine how well we are succeeding at controlling this disease, and the Health Trends™ Diabetes Reports takes an important step in that direction by offering the first national set of clinical benchmarks,” said Gary Puckrein, Ph.D., Executive Director of the National Minority Health Month Foundation in Washington, D.C.

The data used for Quest Diagnostics Health Trends™ reports consist of results of tests performed by Quest Diagnostics laboratories across the United States. Quest Diagnostics’ database of aggregated results of patient testing data is the largest of its kind in the country.

“As the world of healthcare is looking to evidence-based medicine to drive better outcomes, we are proud to be able to use our large clinical database to provide quantitative insights into patient health,” said Surya N. Mohapatra, Ph.D., Chairman and Chief Executive Officer, Quest Diagnostics. “Our Health Trends™ Diabetes Report demonstrates the power of our unique database to show important changes in the way that healthcare providers are helping people control their diabetes.”

Study Methodology and Limitations

The Quest Diagnostics Health Trends™ Diabetes Report encompasses a sample of 14.3 million test results for people with diabetes who visited a health care provider and used a Quest Diagnostics laboratory during the years 2001 – 2005. It does not represent a random sample of the general population. It does not reflect the health of people who did not visit health professionals for diabetes or for whom HbA 1c testing was not ordered. The Report excluded an additional 18.7 million hemoglobin A1c tests performed by Quest Diagnostics during the time period covered by the Report because the physician did not include the most commonly used diagnostic codes for diabetes (ICD-9 codes starting with 250) in the test order.

This study does not follow a cohort, but rather analyzes all test results for patients classified as having diabetes for whom any HbA 1c test was performed over the five-year period, regardless of when their first test occurred during this period. Quest Diagnostics does not have access to clinical data that could help to explain the data trends, such as treatment prescribed.

As recommended by the ADA, the HbA 1c testing method used by Quest Diagnostics throughout the five-year period is certified by the NGSP, the agency that ensures standardization of HbA 1c testing worldwide, making results directly comparable to values from the Diabetes Control and Complications Trial.

Observed trends were consistent across geographic regions, and when analyzed by age and gender, suggested that there were no significant population or demographic changes to account for these trends.

About Quest Diagnostics

Quest Diagnostics is the leading provider of diagnostic testing, information and services that patients and doctors need to make better healthcare decisions. The company offers the broadest access to diagnostic testing services through its national network of laboratories and patient service centers, and provides interpretive consultation through its extensive medical and scientific staff. Quest Diagnostics is a pioneer in developing innovative new diagnostic tests and advanced healthcare information technology solutions that help improve patient care. Additional company information is available at: www.questdiagnostics.com.

The statements in this press release that are not historical facts or information may be forward-looking statements. These forward-looking statements involve risks and uncertainties that could cause actual results and outcomes to be materially different. Certain of these risks and uncertainties may include, but are not limited to, competitive environment, changes in government regulations, changing relationships with customers, payers, suppliers and strategic partners and other factors described in the Quest Diagnostics Incorporated 2005 Form 10-K and subsequent SEC filings.

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Comments from Leading Diabetes Experts:

“These results are a great contribution to our understanding of the state of diabetes care and outcomes in the United States. They indicate that diabetes care has improved over the last five years with glucose-lowering agents, a push to multidisciplinary care, stricter criteria for diabetes diagnosis and public and professional awareness campaigns about the importance of early diagnosis and treating to target.”

Dr. Francine KaufmanKeck School of MedicineUniversity of Southern California

“This is a huge data set with enormous statistical power that helps us understand the state of control of diabetes in the United States. This is valuable information for healthcare professionals, policy makers and payers.”

Dr. David E. GoldsteinUniversity of Missouri Health Sciences Center

“What makes these data so interesting is that they suggest that over time, glucose control is getting better. This is in direct contrast to the National Health and Nutrition Examination Survey (NHANES) data which suggests that diabetes control in the United States population declined through the period of the late 1990s. NHANES provides the context that makes the Quest Diagnostics data from the last five years so interesting.”

Dr. Nathaniel G. ClarkAmerican Diabetes Association

“There is a serious need for timely clinical baselines to determine how well we are succeeding at controlling this disease, and the Health Trends™ Diabetes Reports takes an important step in that direction by offering the first national set of clinical benchmarks.”